The present invention relates to a semiconductor device and method of manufacture thereof, and to a circuit board and an electronic instrument.
In recent years, with the increasing compactness of electronic instruments, semiconductor device packages adapted to high density mounting are in demand. In response to this, surface mounting packages such as a ball grid array (BGA) and a chip scale/size package (CSP) have been developed. In a surface mounting package, a substrate may be used which has formed thereon an interconnect pattern for connection to a semiconductor chip.
In a conventional surface mounting package, since there is a step of providing a protective film to protect the interconnect pattern and so forth, it is has been difficult to improve the productivity.
The present invention solves this problem, and has as its objective the provision of a method of manufacturing a semiconductor device and a semiconductor device manufactured by the method, of a circuit board and of an electronic instrument, having excellent reliability and productivity.
(1) A method of manufacturing a semiconductor device of the present invention comprises:
a first step of interposing an adhesive between a surface of a substrate on which an interconnect pattern is formed and a surface of a semiconductor chip on which electrodes are formed;
a second step of applying energy between the semiconductor chip and the substrate, electrically connecting the interconnect pattern and the electrodes, and making adhesive properties of the adhesive effective in the region of contact with the semiconductor chip while the adhesive spreading out beyond the semiconductor chip; and
a third step of applying energy to the region of the adhesive other than the region of contact with the semiconductor chip.
(2) In this method of manufacturing a semiconductor device,
the adhesive may be thermosetting;
the energy applied in the second step may be pressure and heat; and
the energy applied in the third step may be heat.
The adhesive is cured in the region of contact with the semiconductor chip, and thereafter, the region other than the region of contact is heated and cured. Thus the adhesive is also cured in the region where it spreads out beyond the semiconductor chip. By means of this, the possibility of the adhesive coming apart from the substrate and allowing the ingress of water, leading to migration of the interconnect pattern can also be prevented. Since the adhesive is cured, the inclusion of water can be prevented.
(3) In this method of manufacturing a semiconductor device, the interconnect pattern and the electrodes may be electrically connected by conductive particles dispersed in the adhesive.
Since the interconnect pattern and electrodes are electrically connected by the conductive particles, a semiconductor device can be manufactured by a method of excellent reliability and productivity.
(4) In this method of manufacturing a semiconductor device, before the first step, the adhesive may be previously disposed on the surface of the semiconductor chip on which the electrodes are formed.
(5) In this method of manufacturing a semiconductor device, before the first step, the adhesive may be previously disposed on the surface of the substrate on which the interconnect pattern is formed.
(6) In this method of manufacturing a semiconductor device, in the third step, energy may be applied to a portion of the adhesive at which curing is not completed in the second step.
(7) In this method of manufacturing a semiconductor device, in the third step, the adhesive may be heated by a heating jig.
(8) In this method of manufacturing a semiconductor device, a nonadhesive layer having high nonadhesive properties to the adhesive may be interposed between the heating jig and the adhesive, and the adhesive is heated.
(9) In this method of manufacturing a semiconductor device, the heating jig may be provided with the nonadhesive layer.
(10) In this method of manufacturing a semiconductor device, the nonadhesive layer may be disposed on the adhesive.
(11) In this method of manufacturing a semiconductor device, in the third step, energy may be applied to the adhesive without contacting the adhesive.
(12) This method of manufacturing a semiconductor device may further comprise:
a reflow step in which solder balls connecting to the interconnect pattern are formed on the substrate,
wherein the third step may be carried out in the reflow step.
(13) This method of manufacturing a semiconductor device may further comprise:
a reflow step in which in addition to the semiconductor chip, another electronic component is electrically connected to the interconnect pattern;
wherein the third step may be carried out in the reflow step.
(14) In this method of manufacturing a semiconductor device, after the third step, the substrate may be cut in a region other than a region in which the adhesive contacts with the semiconductor chip.
(15) In this method of manufacturing a semiconductor device, in the second step, the adhesive may be caused to surround at least a part of a lateral surface of the semiconductor chip.
Since the adhesive covers at least a part of the lateral surface of the semiconductor chip, not only is the semiconductor chip protected from mechanical damage, but also water can be prevented from reaching the electrodes, and corrosion can be prevented.
(16) In this method of manufacturing a semiconductor device, the adhesive may be provided before the first step at a thickness greater than the interval between the semiconductor chip and the substrate after the second step, and may spread out beyond the semiconductor chip by applying pressure between the semiconductor chip and the substrate in the second step.
(17) In this method of manufacturing a semiconductor device, the adhesive may include a shading material.
Since the adhesive includes a shading material, light can be prevented from reaching the surface of the semiconductor chip having the electrodes, and so malfunction of the semiconductor chip can be prevented.
(18) A method of manufacturing a semiconductor device according to the present invention comprises:
a first step of interposing an adhesive between a surface of a substrate on which an interconnect pattern is formed and a surface of a semiconductor chip on which electrodes are formed;
a second step of electrically connecting the interconnect pattern and the electrodes, and curing the adhesive at least in a position between the semiconductor chip and the substrate while the adhesive spreading out beyond the semiconductor chip; and
a third step of cutting the substrate in a region in which the adhesive spreads out beyond the semiconductor chip.
According to the present invention, the adhesive is cut after it is provided spreading out beyond the semiconductor chip. Thus, there is no requirement for accurate positioning with respect to the semiconductor chip at the same size as the semiconductor chip. Since the adhesive is cut in the region spreading out beyond the semiconductor chip together with the substrate, the entire surface of the substrate is covered by the adhesive so that migration and the like of the interconnect pattern can be prevented.
(19) In this method of manufacturing a semiconductor device, the adhesive may be a thermosetting adhesive, and heat may be applied to the adhesive in the second step.
(20) In this method of manufacturing a semiconductor device, the adhesive may be a thermoplastic adhesive, and the adhesive may be cooled in the second step.
(21) In this method of manufacturing a semiconductor device, the interconnect pattern and the electrodes may be electrically connected by conductive particles dispersed in the adhesive.
(22) In this method of manufacturing a semiconductor device, before the first step, the adhesive may be previously disposed on the surface of the semiconductor chip on which the electrodes are formed.
(23) In this method of manufacturing a semiconductor device, before the first step, the adhesive may be previously disposed on the surface of the substrate on which the interconnect pattern is formed.
(24) In this method of manufacturing a semiconductor device, in the third step, a cutting position may be in a region outside an end of the interconnect pattern of the substrate.
(25) In this method of manufacturing a semiconductor device,
in the second step, the whole of the adhesive may be cured; and
in the third step, the cured adhesive may be cut.
Since the cured adhesive is cut, the cutting can be carried out easily.
(26) In this method of manufacturing a semiconductor device, in the second step, the adhesive may be caused to surround at least a part of a lateral surface of the semiconductor chip.
Since the adhesive covers at least a part of the lateral surface of the semiconductor chip, not only is the semiconductor chip protected from mechanical damage, but also water can be prevented from reaching the electrodes, and corrosion can be prevented.
(27) In this method of manufacturing a semiconductor device, the adhesive may be provided before the first step at a thickness greater than the interval between the semiconductor chip and the substrate after the second step, and may spread out beyond the semiconductor chip by applying pressure between the semiconductor chip and the substrate in the second step.
(28) In this method of manufacturing a semiconductor device, the adhesive may include a shading material.
Since the adhesive includes a shading material, light can be prevented from reaching the surface of the semiconductor chip having the electrodes, and so malfunction of the semiconductor chip can be prevented.
(29) A semiconductor device according to the present invention comprises:
a semiconductor chip having electrodes; a substrate having an interconnect pattern; and a thermosetting adhesive;
wherein the electrodes and the interconnect pattern are electrically connected; and
wherein the adhesive is interposed between a surface of the substrate on which the interconnect pattern is formed and a surface of the semiconductor chip on which the electrodes are formed, and spreads out beyond the semiconductor chip, and the whole of the adhesive is cured.
According to the present invention, the adhesive is also cured in a region outside that of contact with the semiconductor chip. Thus, the possibility of the adhesive coming apart from the substrate and allowing the ingress of water, leading to migration of the interconnect pattern can be prevented. Also, since all of the adhesive is cured, the inclusion of water can be prevented.
(30) In this semiconductor device, conductive particles may be dispersed in the adhesive to form an anisotropic conductive material.
Since the interconnect pattern and electrodes are electrically connected by the anisotropic conductive material, the reliability and productivity are excellent.
(31) In this semiconductor device, the anisotropic conductive material may be provided to cover the whole of the interconnect pattern.
(32) In this semiconductor device, the adhesive may cover at least a part of a lateral surface of the semiconductor chip.
Since the adhesive covers at least a part of the lateral surface of the semiconductor chip, the semiconductor chip is protected from mechanical damage. Additionally, since the semiconductor chip is covered by the adhesive as far as a position remote from the electrodes, water can be prevented from reaching the electrodes, and corrosion can be prevented.
(33) In this semiconductor device, the adhesive may include a shading material.
Since the adhesive includes a shading material, light can be prevented from reaching the surface of the semiconductor chip having the electrodes, and so malfunction of the semiconductor chip can be prevented.
(34) A semiconductor device according to the present invention is manufactured by the above-described method.
(35) On a circuit board according to the present invention, the above-described semiconductor device is mounted.
(36) An electronic instrument according to the present invention has the above-described circuit board.